The present invention relates to an electric booster, and more particularly, to an electric booster capable of preventing a part damage by an excessive screw rotation when a braking force is released.
In general, an electric booster drives a motor to press a master cylinder, and the master cylinder generates a brake pressure. Such an electric booster includes a motor, a screw rotated by the motor, a nut linearly moved by the screw, and a piston generating a brake pressure while being moved by the nut. In such an electric booster, the screw is only rotated, and the nut is only linearly moved. Therefore, a ring is assembled to the screw, in order to prevent a part separation.
However, when precise control is not performed while a brake force is released, the screw may be additionally rotated even though the nut is returned to the original state. The additional rotation of the screw may excessively move the nut, thereby causing a damage of the part. Thus, there is a demand for a device capable of solving such a problem.
The related art is disclosed in Korean Patent Publication No. 2012-0045597 published on May 9, 2012 and entitled “Electric booster-type brake”.